The present invention relates to a novel heat-sensitive color transfer ribbon, and more particularly to a heat-sensitive color transfer ribbon suited for producing color copies in a thermal recording system.
In recent years, a thermal printer and a facsimile of thermal recording type are commonly employed from the viewpoint of the advantages such as maintenance free and low cost. A heat transfer ribbon or carbon paper having a layer of a heat-transfer ink composition on a foundation is usually employed as a recording medium in a thermal printer and thermal facsimile, and various improvements of the ribbon and carbon paper, e.g. in fastness of the transferred image, are proposed. A known thermal printer and thermal facsimile are of the type producing a duplicate of single color such as black or blue, and there is desired the development of a thermal color printer and thermal color facsimile.
As a color recording system, there are known an impact recording system as seen in a usual typewriter in which a cloth ribbon, e.g. a ribbon coated with inks of two colors, is employed; and an ink-jet recording system in which inks are jetted by employing two or more ink-jet heads. The former has the disadvantages of a large noise and slow recording speed. Also, the latter has the disadvantages that troubles such as choking of a nozzle for jetting out an ink are easy to occur and that since the amount of ink jetted must be controlled, the apparatus itself becomes intricate and expensive and is also complicated to operate.
On the other hand. there has been lately proposed a color recording system applying the principles of color television and color phototelegraphy. FIG. 1 is a diagrammatic view showing such a color recording system. A color original 1 is subjected to color separation by color separation filters 21, 22 and 23. The respective color-separated images are then read by photoelectric tubes 31, 32 and 33, and are converted into yellow signal Y, cyan signal C and magenta signal M. The signals are transmitted from a transmitter 4 to a receiver 5 at which the signal separation is conducted again. The signals are transmitted to a printer 6 to reproduce a color image which closely resembles the original, on a copy sheet 7. Recording machines applicable to such a system have been proposed and developed. The application of a thermal printer as a printer 6 is advantageous in points of low cost, easiness in operation, low noise and high printing speed
It is an object of the present invention to provide a novel recording medium applicable to a thermal printer in a color recording system as mentioned above.
A further object of the invention is to provide a heat-sensitive transfer ribbon intended for the application to a thermal color recording system by which color image closely resembling a color original can be reproduced on a copy sheet.
These and other objects of the present invention will become apparent from the following description with reference to the accompanying drawings.